The present invention relates to wound dressings or like appliques. Wound dressings comprising adhesively coated, thin polymeric films have become popular because they allow the wound to breathe. However, because they are thin, they are difficult to apply to the wound without wrinkling or sticking on themselves. Also, it is difficult to separate the wound dressing from its release liner.
Artisans have attempted to overcome this by cutting a perforation line in the polymeric film over a solid cut line in the release liner to thereby define a polymeric wound covering portion, a release liner covering only the wound covering portion, and offal comprising the perimeter portion of the film and the perimeter portion of the release liner. In use, one first peels away the center cut portion of the release liner, leaving the adhesive coating on the wound covering portion exposed. One then grips the offal portion on opposite ends to facilitate firm application of the wound covering portion to the wound area. The offal is then peeled away by tearing the film along the perforation line.
There are several problems with such bandages. First, it is difficult to separate the central portion of the release liner from the wound covering portion. There is a tendency to tear the polymeric film along its perforation line when the central portion of the release liner is removed. This is especially true if the perforation line is too weak, i.e., if the bridges between perforations are too short for a given thickness of polymeric film.
Alternatively, if the perforation line is too strong, it is difficult to tear the offal away from the wound covering portion of the film when it is adhered to the skin or other substrate. There is a tendency to lift the edge of the wound covering from the person's skin when one attempts to peel away the offal.
One attempt to obviate these drawbacks is disclosed in U.S. Pat. No. 4,485,809 to Dellas issued Dec. 4, 1984. Dellas offsets the cut line in the release liner outwardly from the perforation line in the polymeric film, theoretically making it easier to peel away the central portion of the release liner without simultaneously peeling away the wound covering portion of the polymer film. However, Dellas requires the use of two separate die cuts in order to manufacture his wound dressing. This makes it a more costly product.